Solutions by everydaycalculation.com
This multiplication involving fractions can also be rephrased as "What is 21/60 of 21/56?"
2160 × 2156 is 21160.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/60×21/56 21/60×42/56 63/60×21/56 21/60×63/56
© everydaycalculation.com